Terahertz Nanofocusing with Cantilevered Terahertz-Resonant Antenna Tips.

  title={Terahertz Nanofocusing with Cantilevered Terahertz-Resonant Antenna Tips.},
  author={Stefan Mastel and Mark B. Lundeberg and Pablo Alonso-Gonz{\'a}lez and Yuanda Gao and Kenji Watanabe and Takashi Taniguchi and James C. Hone and Frank H. L. Koppens and Alexey Yu Nikitin and Rainer Hillenbrand},
  journal={Nano letters},
  volume={17 11},
We developed THz-resonant scanning probe tips, yielding strongly enhanced and nanoscale confined THz near fields at their tip apex. The tips with length in the order of the THz wavelength (λ = 96.5 μm) were fabricated by focused ion beam (FIB) machining and attached to standard atomic force microscopy (AFM) cantilevers. Measurements of the near-field intensity at the very tip apex (25 nm radius) as a function of tip length, via graphene-based (thermoelectric) near-field detection, indicate… 

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